2.11- Spectroscopy

Question 0

What can high resolution mass spectrometry be used to determine?

Answer 0

The molecular formula of a compound from the accurate mass of the molecular ion

Question 1

Define molecular ion?

Answer 1

Molecule with one electron knocked off (it is both an ion and a free radical)

Question 2

What is infrared spectroscopy?

Answer 2

Certain groups in a molecule absorb infra red radiation at characteristic frequencies

Complicated spectra can be obtained to provide information about the types of bonds present in a molecule

Question 3

Above and below 1500cm-1 in an infrared spectroscopy reading?

Answer 3

Above 1500cm-1- functional group identification

Below 1500cm-1- fingerprinting:
This part of the spectrum is unique for every compound and can be used as a fingerprint

A computer will compare the IR spectra against a database of known pure compounds to identify the compound

Question 4

What are rogue absorptions?

Answer 4

Indicators of impurities